--  @testpoint:opengauss关键字routine(非保留)，作为函数名
--关键字不带引号-成功
drop function if exists routine;
create function routine(i integer)
returns integer
as $$
begin
    return i+1;
end;
$$ language plpgsql;
/
--清理环境
drop function routine;

--关键字带双引号-成功
drop function if exists "routine";
create function "routine"(i integer)
returns integer
as $$
begin
    return i+1;
end;
$$ language plpgsql;
/
drop function "routine";

--关键字带单引号-合理报错
drop function if exists 'routine';
create function 'routine'(i integer)
returns integer
as $$
begin
    return i+1;
end;
$$ language plpgsql;
/

--关键字带反引号-合理报错
drop function if exists `routine`;
create function `routine`(i integer)
returns integer
as $$
begin
    return i+1;
end;
$$ language plpgsql;
/